Powerwall 2 comes with a storage capability of 13.5KWh of electricity [ 5 ] – enough to power the average U . K home for approximately 3 days . [ 6 ]
Powerwall batteries were introduced temporarily by Tesla in Puerto Rico during the aftermath of Hurricane Maria . [ 7 ] Later it was claimed by Elon Musk , the CEO , that the company could supply permanent batteries with renewable resources to store and supply the whole island with reliable power , both during storms and during normal operation . [ 8 ] Musk exemplifies companies ’ readiness to implement such technology on ever-larger scales .
However , the failure of major cross-country power lines poses the greatest threat to power supplies over large areas and , consequentially , larger scale batteries are being developed to supply power regionally . In September 2016 , South Australia was hit by one of the worst storms in decades , leading to over 1.7 million residents over large areas of Adelaide without power . Contracted by the government , Telsa had the 126 MWh battery operational by December 2017 , within 100 days . [ 9 ] The battery – the world ’ s largest – is supplied energy by Hornsdale Wind Farm and used both during normal grid operations and during power outages at major power stations . Less than a month after installation , the batteries were put to the test twice when power stations in neighbouring states had a sudden drop in output . The system took only seconds to kick in and supply energy to homes , a record for local grid responses . [ 10 ] As of publication , the battery has responded to dozens of incidents , each in a matter of seconds , ensuring a huge increase in reliability of power across South Australia . The real test will come if a large-scale natural disaster hits the area . It is evident that future projects will emulate Tesla ’ s success , combatting power outages around the globe .
Alongside battery technology , micro-grids are increasingly being combined with renewables to increase grid reliability worldwide . Micro-grids are smaller electrical grids with their own unique power supply and demand , that can act separately or in conjunction with the main grid . Micro-grids insulate themselves from the main grid in the event of failure and can vary in size from a house to a whole city or state .
In 2012 , India experienced one of the worst blackouts in history with 670 million people going without power due to poor infrastructure . [ 11 ] To combat this , the government is considering combining micro-grids with increased usage of renewables and battery technology to localise power . This initiative attempts to reduce reliance on a countrywide power grid system , a system which is susceptible to failure , due to its sheer size and the increasing demand for energy in the country .
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